Abstract: A unique session identifier may be utilized to announce the availability of an electronic programming guide to users of an enhanced television distribution system. In some embodiments, the unique session identifier may be utilized in a variety of systems to provide a uniform way of recognizing the availability of an electronic programming guide in conjunction with enhanced television distribution systems.

Abstract: An enhanced television broadcast system may enable the transmission and reception of a real-time event when a new program is about to begin. The real-time event may control access to enhancements from the program that is ending. In some embodiments, these real-time events may constitute triggers that are included within packets transmitted in an Internet Protocol multicast. As one example, the trigger may include a Uniform Resource Locator in the form of a tv: protocol that automatically causes the television display to go to full screen television.

Abstract: Enhanced television broadcasts including triggers with expires attributes may be utilized in a variety of situations where the expires attribute may adversely affect the utilization of the trigger. For example, in situations where the broadcast is recorded, playback may be enabled even after the trigger expiration. Similarly, local affiliates or FNOCs may rebroadcast enhanced television content by adjusting the expires attributes of the original trigger.

Abstract: An enhanced television recorder and player includes a trigger inserter unit that inserts triggers into vertical blanking intervals of audio/video signals. The triggers point to resources that are stored in a storage medium or are available from a network, where the triggers, audio/video signals, and resources together can comprise a Transport Type B transmission. The audio/video signals having triggers in the vertical blanking intervals are stored in the storage medium, and during playback by a stream simulator unit, simulate a Transport Type A transmission, transformed from the Transport Type B transmission. Requested resources may be retrieved from the storage medium or from the network by a proxy unit of the receiver unit.